While the present invention is primarily concerned with emergency sump pumps, features thereof can be utilized in pumps for other purposes.
Two important requirements of emergency sump pumps are that they be reliable, that is, they perform when required, and that they have high performance. For example, when storm water is accumulating in a sump, it is very important that that water be removed to prevent the damage that would otherwise be caused by the water overflowing the sump. Since such emergency pumps are operated only infrequently the existence of a condition which would cause pump failure may not be detected until the emergency occurs. Thus the feature of reliability is most significant. When the emergency occurs, water may be entering the sump quite rapidly, thus the necessity for high performance.
Another important attribute for a sump pump is that of adaptability to a wide variety of installation requirements. The configuration, size, etc., of the sump will be different in almost every instance. In fact, in some instances the basement floor drain may be the structure that might be referred to as the sump. Also, the pump capacity, the type of electric power to be employed, etc., will vary from job to job. To meet the varied requirements with a minimum of inventory, it is important to the pump supplier to have pump components which can be varied to meet the requirements of a particular job. Thus, for example, on one job the purchaser may want to use a 12 volt motor powered by a standby battery while on the next job a person may want to utilize 110 volt house current. If the supplier can merely interchange basic electric motors, and render them waterproof and utilizable with the other pump components, it is not necessary that the supplier stock every type of pump that might be required. This is only illustrative and the same applies to other components necessary to satisfy various installation requirements.
As is almost always the case, the element of cost also is an important factor to be considered. The business is a competitive business and where the manufacturing cost of the emergency sump pump is high, it may be that the product cannot be sold in competition with units of other designs. For example, many sump pumps utilize special castings for the pump, etc.
Thus, the object of the present invention is to produce a versatile, relatively low cost emergency sump pump which will have a high degree of reliability. Various features of the present invention contribute toward this end. For example, standard electric motors of diverse electrical characteristics (voltage, power, etc.) are converted into waterproof motors by substantially only the addition of a pair of end caps. These end caps also provide the necessary standard mountings for mating with the other pump components. This waterproof motor is then mounted inside a length of pipe of a standard size. Reducers on each end of that length of pipe provide for the adaptability of the pump to mate with other standard sizes of pipe utilized for the intake and discharge connections. At the intake end provision is made for the mounting of a screen when desired, which screen is formed from a standard length of pipe and also may serve as the pump support.
An important feature of the invention is that the water being pumped flows about the motor shell. Thus when in use, the motor is constantly being cooled by that water. This increases the efficiency and permits the motor to be worked at a capacity that otherwise might cause excessive heating. The spacers used to position the pipe through which the water is flowing serve as cooling fins. This arrangement, in conjunction with the type of impeller employed, also prevents the downflow of water which occurs, in the absence of a check valve, when the motor is turned off from causing an undesired, and undescribable, rotation of the motor. Pumping efficiency also is assisted in one embodiment by providing a readily accessible adjustment by which the spacing between the inner end of the intake tube and the impeller may be established after assembly.
Embodiments of the invention are relatively small and lightweight considering their pumping capacity. Their structure is such that maintenance is easily performed, both in the shop and in the field.
In one embodiment the pump is mounted externally of the sump and provision is made for automatically dropping the pump into the sump when the necessity for water removal occurs.
Other features of the invention will be mentioned and will be apparent from the following description of specific embodiments.